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Porch Pup
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Posts posted by mcratchet1

  1. 2006 mr688s just replaced d2 because not building air on idle  at startup its constantly leaking air out of ehaust port. So i have to idle up to build air but once air is built up it stops also getting alot of water in tanks at the end of the day. Is this signs of air compressor failing i replaced it 2 years ago with bendix reman Any insight i would be grateful!!

  2. so i have a 2006 mr688s (032711) the jack operates great lifting the cab but when i want to go down it will pump up and get solid and not move. The only way to lower cab is to open the line, there's no leaks or damage visible. My question is there a relief valve inside maybe hanging up? Has anybody had this problem before? Thanks!!

  3. Hey guys just wondering if the newer mack mru 2015+ with t310 and t318 transmissions, if the clutch still gets adjusted the same way as the older mr688s models?

    By old way i mean put a wrench on clutch adjusting bolt with prybar have someone step on clutch and push in spring to turn the bolt


  4. ok found high/low beam relay bad changed been running with no problems for a month now did same thing 2x today also this morning truck would not start. When i turned key only heard buzzing coming from these 4 relays. Does anybody know what these control? im guessing one has to be starter i cycle the key a few times then it cranks i checked to the wire had 11.50 but when i turned key switch dropped to 5.5 volts now truck will not start going to just start tracing wires unless someone could help a brother out 


    IMG_8425 (1).jpg

  5. yes, the only thing i do not have a pin tester to check relays, but the did have good scratches and fit tight

    we are a small private pump company we have 7 mack trucks

    I called mack for a diagram of the fuse and relay layout in the dog box but they said they cannot give me that info they are never helpful

    032711 is the last 6 of vin do you have access to fuse and relay location?   



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